Single Page View of Word Doc at 100% Zoom

I have a single document that for some reason will not display at 100% as a single page. If I go to View and select 100% (or Zoom and select 100%), the document appears as 2 pages. If I select “One Page”, the Zoom changes to 78%. As close as I can get for a single page display is 101% zoom. This is the only document that behaves this way, and it started this behavior recently.